There is a need among skin divers for a game bag that has some type of rigid opening and closure mechanism but that is simple enough that it will not rust or clog, and can be operated by one hand.
Current dive bags come in a variety of configurations ranging from a simple bag with no mouth closure at all to bags with clips or other devices which hold the handles together. Bags with no closure at all, and no means of holding the mouth of the bag open to insert game, are virtually impossible to use with anything other than inert forms of game such a shellfish. A speared fish pinned to the bottom or otherwise engaged at best only temporarily by one hand is virtually impossible to successfully transfer into a limp bag with no rigid mouth opening. Invariably while trying to cause the mouth of the bag to open with one hand, by drawing it back and forth in the water in all manner of gyrations, the fish escapes from the spear and swims off somewhere to die out of reach.
Other closures having latches effectively avoid the above stated problem, but vary in their degree of simplicity and the ability of the user to open and close the bag with only one hand, which is a virtual necessity when hunting with a spear or spear gun.